<p>给定两个单词&nbsp;<code>word1</code>&nbsp;和<meta charset="UTF-8" />&nbsp;<code>word2</code>&nbsp;，返回使得<meta charset="UTF-8" />&nbsp;<code>word1</code>&nbsp;和&nbsp;<meta charset="UTF-8" />&nbsp;<code>word2</code><em>&nbsp;</em><strong>相同</strong>所需的<strong>最小步数</strong>。</p>

<p><strong>每步&nbsp;</strong>可以删除任意一个字符串中的一个字符。</p>

<p>&nbsp;</p>

<p><strong>示例 1：</strong></p>

<pre>
<strong>输入:</strong> word1 = "sea", word2 = "eat"
<strong>输出:</strong> 2
<strong>解释:</strong> 第一步将 "sea" 变为 "ea" ，第二步将 "eat "变为 "ea"
</pre>

<p><strong>示例 &nbsp;2:</strong></p>

<pre>
<b>输入：</b>word1 = "leetcode", word2 = "etco"
<b>输出：</b>4
</pre>

<p>&nbsp;</p>

<p><strong>提示：</strong></p>
<meta charset="UTF-8" />

<ul>
	<li><code>1 &lt;= word1.length, word2.length &lt;= 500</code></li>
	<li><code>word1</code>&nbsp;和&nbsp;<code>word2</code>&nbsp;只包含小写英文字母</li>
</ul>
